Small Engines (Lawn Mowers, etc.): Chainsaw, monster snowstorm, carbon buildup

Question
Hi, I have been operating chainsaws for 30 years but am totally confused about an issue I have at present. I have a 2 year old Husky 455 saw and it has been the best I have had so far. I live in colorado and we had a monster snowstorm Saturday and high winds and a 100' tree crashed down on my bridge.  I got my trusty saw out and it was running rough but I was able to cut the tree into pieces and drag it off with my truck. My problem is the saw is refusing to run at high speed so I did my normal tune up and gapped and put a new plug in, replaced and cleaned the carb, put a new air filter on and dumped the gas and mixed a new batch. The saw starts easily and idles no problem but will not run at high speed so I fiddled a little with the carb adjustmets and still cannot get it to work properly. I read the manual and it mentions operating it at lower temps might require a special cover that keeps the heat inside for proper operating temp. I noticed when I replaced the plug that the top of the piston has a black carbon buildup and was thinking maybe thats an issue.

Thanks in advance, Ray

Answer
Hello Raymond:

>>From your Description it Sounds like the Exhaust Port or Muffler May be Restricted with Carbon or the Carburetor Requires Adjusting.
>>The Following is a Basic Instruction File for Doing a Diagnostic on the Engine for this Problem. Any Input is Appreciated.
>>**Remove the Muffler and Make Sure the Exhaust Port is Clear.
>>If it is, then Try to Start the engine with the Muffler Off.
>>If it Starts and Runs Properly, then Clean the Spark Arrestor Screen in the Muffler or Replace the Muffler if Required.
>>Please, Do Not Hesitate, If you Hit a Snag, if I Missed Something or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

>>PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John